The police have arrested a second person accused of being involved in the bomb attack on a London underground train on September 15. The 21-year-old man was arrested in the west London suburb of Hounslow just before midnight on Saturday, the Metropolitan Police force said in a statement.

He was detained under Britain’s Terrorism Act and taken to a south London police station.

The Kent Police on Saturday arrested the first suspect, an 18-year-old in Dover. Twenty-nine people were injured in the explosion on Friday. The Islamic State group on Friday had claimed responsibility for the attack on a train in London.

The London Ambulance Service said none of the injuries commuters sustained were serious or life-threatening. Local authorities said most of the injuries seemed to have been caused by flash burns.